1. Field of the Invention
The present invention relates to a transmitting apparatus for use in non-geostationary satellites, which is mounted in a non-geostationary satellite of a satellite communications system to carry out intersatellite communication between a geostationary satellite and the non-geostationary satellite (revolving satellite).
2. Description of the Prior Art
A transmitting apparatus of this type for non-geostationary satellites is mounted in a non-geostationary satellite of a satellite communications system to carry out intersatellite communication between a geostationary satellite revolving around the Earth along a geostationary orbit separated from the surface of the Earth by a first given distance in a stationary state relative to the surface of the Earth, and the non-geostationary satellite revolving around the Earth along a non-geostationary orbit separated from the surface of the Earth by a second given distance smaller than the first given distance in a non-stationary state relative to the surface of the Earth (in other words, in a state of motion relative to the surface of the Earth).
Such a transmitting apparatus for non-geostationary satellites is usually equipped with a transmitting section which is supplied with power and sends signals to a geostationary satellite along the path between the non-geostationary satellite and the geostationary satellite.
In the case of a non-geostationary satellite intended for intersatellite communication with a geostationary satellite, in order for the non-geostationary satellite moving near the surface of the Earth to communicate with the geostationary satellite in a geostationary orbit, it becomes necessary to send a signal with a higher power flux density (PFD) from the non-geostationary satellite to the geostationary satellite than for communication between the non-geostationary satellite and an Earth station. As the Earth approaches the path between the geostationary satellite and the non-geostationary satellite, however, the Earth is exposed to the signal with the higher PFD, which is not compliant with the restrictions on the PFD prescribed by the Radio Law.